Net Ionic Equations
Chemistry 2013
Name ________________
Net ionic equations are equations that only show the elements that undergo a chemical change in the reaction. When two liquids form a solid, this
is a chemical change. The precipitate formed is a new and different chemical so that is included in the net ionic equation. The rest of the ions in
the solutions are just dissolved in solution and aren’t involved in making the precipitate These are called spectator ions, which remain as ions in the
solution. Spectator ions are omitted in a net ionic equation.
How do you know which elements make up the precipitate?
1. First, exchange the cations and write the compounds that could be formed.
2. Determine which compound forms a solid. (These are insoluble in the aqueous solution.)
• Look it up on a solubility chart.
• Read the solubility rules
O’Ryan
Chemistry 2013
Example
Write the net ionic equation for a mixture of solutions of silver nitrate and lithium bromide. Ag+ + NO3 + Li+ + BrThis is a double replacement reaction. Both reactants are soluble, so everything ionizes (exist as ions in the solution). If anything is formed, it will come from exchanging
the two cations to get LiNO3 and AgBr. Check on the table or read the solubility rules to see If either of them is insoluble. If one of them is, a precipitate will be formed,
and the ions that react to form it will be in our net ionic equation. The other ions are spectators and should be omitted.
All nitrates are soluble, so LiNO3 is NOT the precipitate. Li, NO3 and LiNO3 are the spectator ions. Since halogens are soluble except those containing silver, mercury, or
lead, we can conclude that the precipitate AgBr, and our net ionic equation looks like this: Ag+(aq) + Br-(aq)  AgBr(s)
Net Ionic Equations Practice Problems
Write balanced ionic and net ionic equations (NIE) for each of the following reactions. The first one is done for you.
1.
2NaCl(aq)
+
Pb(NO3)2(aq)
→
PbCl2(s) +
2NaNO3(aq)
2+
NIE:
2Cl (aq)
+
Pb (aq)
→
PbCl2(s)
2.
NIE:
Na2CO3(aq)
2CO3 (aq)
+
+
FeCl2(aq)
2+
Fe (aq)
→
→
FeCO3(s) +
FeCO3(s)
2NaCl(aq)
3.
NIE:
K2(C2O4)(aq)
2C2O4 (aq)
+
+
CaCl2(aq)
2
Ca +(aq)
→
→
KCl(aq) +
Ca(C2O4)(s)
Ca(C2O4)(s)
4.
NIE:
(NH4)3PO4(aq)
32PO4 (aq)
+
+
Zn(NO3)2(aq)
2+
3Zn (aq)
→
→
NH4NO3(aq)
Zn3(PO4)2(s)
+
5.
NIE:
3LiOH(aq)
3OH (aq)
+
+
FeCl3(aq)
3+
Fe (aq)
→
→
LiCl(aq) +
Fe(OH)3(s)
Fe(OH)3(s)
6.
NIE:
Mg(NO3)2(aq)
2+
Mg (aq)
+
+
Na2CrO4(aq)
2CrO4 (aq)
→
→
NaNO3(aq)
MgCrO4(s)
+
7.
NIE:
BaBr2(aq)
2+
Ba (aq)
+
+
Na2SO4(aq)
2SO4 (aq)
→
→
BaSO4(s) +
BaSO4(s)
2NaBr(aq)
8.
2AgNO3(aq)
+
MgI2(aq)
→
+
+
2I (aq)
→
NIE:
2Ag (aq)
(your final answer would be: Ag+(aq) + I-(aq) → AgI(s))
2AgI(s) +
2AgI(s)
9.
NIE:
Ni(NO3)2(aq)
2+
Ni (aq)
O’Ryan
+
+
2NaOH(aq)
2OH (aq)
→
→
Ni(OH)2(s)
Ni(OH)2(s)
Zn3(PO4)2(s)
MgCrO4(s)
Mg(NO3)2(aq)
+
2NaNO3(aq)